A U.S. Customs and Border Protection pilot was killed Monday morning when a helicopter crashed in a field in the East County community of Potrero, north of state Route 94, officials said. Cal Fire officials were notified of the crash just before 11:20 a.m. The helicopter — a Eurocopter AS350 — went down during a border security mission near Round Potrero Road in a rural area near farmland, said Cal Fire Capt. Mike Cornette and CBP officials. The pilot, whose name was not released, was killed. No one else was on board when it crashed, Cornette said. The crash did not spark a fire. A CBP spokesperson said the pilot was an air interdiction agent with the agency’s air and marine operations, a separate component of the agency. The National Transportation Safety Board will be in charge of the investigation. Cal Fire officials referred all further questions to the federal government on Monday evening. CBP said additional information would be released as it became available. Staff writers Caleb Lunetta and Alexandra Mendoza contributed to this report.